This invention relates to an improvement of an inspection device for inspecting continuity of terminals in a connector.
Connectors are used to join two or more sections of the electrical wiring harness together to be installed into the body-work of a vehicle. Typical connectors have a terminal block in a connector housing where several terminals are grouped. The terminal block consists of either a row of male terminals or a row of female terminals. The connector may have a locking device to ensure a good attachment, and electrical connections between the male and female connectors will be achieved by means of firmly engaging them by the locking device. The escape of a terminal pin from the terminal block and poor continuity between terminals and wires are not allowable for the connector in use and such troubles should be avoided anyway.
With respect to this problem, to inspect terminals prior to installation is a reasonable and preferable counter-measurement. Various inspection devices for inspecting continuity of terminals have been developed for this purpose. For example, Japanese Utility Model Registration Examined Publication No. 8221/1980 and Japanese Patent Unexamined Prepublication No. 5383/1990 both disclose an inspection device for inspecting continuity of the terminals in a multi-pin connector. Wiring harness complexity, in a modern vehicle, requires the use of many of these multi-pin connectors having several terminals therein. The inspection device enables simultaneous inspection for mechanical connection and electrical connection, which is now described below.
Japanese Utility Model Registration Examined Publication No. 8221/1980 discloses the inspection device S as shown in FIGS. 1 and 2. FIG. 1 is a perspective view showing the inspection device of which sectional view is shown in FIG. 2. The inspection device S comprises a base plate 1, a holding plate 2, an inspector body 3 and a pair of cams 4. The holding plate 2 stands at a side of the base plate 1 and the inspector body 3 is slidably mounted on the base plate 1. The inspector body 3 moves on the base plate 1 by the cams 4 so as to approach and separate from the holding plate 2.
A connector catch 5 is formed on the holding plate 2 to receive a connector A to be inspected. The connector A has terminals 6 fitted to the end of wires 7 and the terminals 6 are held in a terminal accommodating chamber 11. The connector catch 5 is provided with an opening 5a through which the wires 7 are led to the outside. At the opposite side of the base plate 1 to the holding plate 2, a shaft fixture plate 15 is attached to fix a pair of slide shafts 8, 8. In this event, each slide shaft 8 is secured to the shaft fixture plate 15 at one ends thereof. The other end of the slide shaft 8 is supported by the holding plate 2. Each of the slide shafts 8, 8 penetrates through the inspector body 3 and compression coil springs 9 are wound in helical fashion around a portion of the slide shafts 8, 8, respectively, exposed to the outside of the inspector body 3. The compression coil springs 9 force the inspector body 3 to the fixture plate 15 in the direction apart from the connector catch 5.
The inspector body 3 consists of two inspector body blocks 3a and 3b which are formed together. An engaging hollow portion 10 is formed on the inspector body block 3b to engaging the connector A. The engaging hollow portion 10 faces to the connector catch 5 on the holding plate 2 and has a plurality of inspection pins 12 which are equal in number to the terminals 6 held in the terminal accommodating chamber 11 of the connector A. Each of the inspection pins 12 consists of a lead pin portion 12a and a tail pin portion 12b (see FIG. 2) passing through a penetration passage 13 formed in the inspector body 3.
The lead pin portion 12a passes through a compression coil spring 14 wound therearound. The compression coil spring 14 forces the lead pin portion 12a in the direction to the holding plate 2. Similarly, the tail pin portion 12b passes through a compression coil spring 16 wound therearound and is forced in the direction to the holding plate 2. The rear end of the lead pin portion 12a is not touched to the front end of the tail pin portion 12b when the connector A is not on inspection while the lead pin portion 12a contacts the tail pin portion 12b during continuity inspection of the terminals in a manner described below.
Cam catches 17 are formed on each side of the inspector body 3, where cam surfaces 4a, 4a of the cams 4 contact respectively.
Each of the cams 4 is rotatably supported by a pair of cam supporters 18, 18 through a shaft 19. The cams 4 are connected through an arm 20 which has a cam lever 20a projected from a central portion thereof. The cam lever 20a comprises a spherical knob at one end thereof, extremely away from the arm 20.
Inspection of continuity of the connector A by using the above mentioned inspection device S first requires to attach the connector A to the connector catch 5. Subsequently the arm 20 is moved along a sector track about the shaft 19, thereby the cams 4 slide on the cam catches 17 to push the inspector body 3 towards the connector A. As the inspector body 3 approaches the connector A, a front surface, facing to the inspector body 3, of the connector A gets into the engaging hollow portion 10. Each terminal pin 6 in the connector A abuts the lead pin portion 12a when the connector A engages the engaging concavity 10.
The inspector body 3 further approaches the connector A against the spring force of the compression coil springs 14 and 16 when the cam lever 20a is fully turned. As a result, the lead pin portion 12a is withdrawn in the inspector body 3 to contact the tail pin portion 12b. The inspection of continuity is made with the lead and tail pin portions 12a and 12b being in contact. After completion of the inspection of continuity, the connector A can be removed from the inspector body 3 by means of turning the arm 20 in the reverse direction. The facing surface of the connector A to the engaging hollow portion is away from the engaging hollow portion 10 due to the spring force of the compression coil spring 9. The terminals 6 are thus off the inspection pins 12 allowing picking the connector A out of the connector catch 5.
Next, an inspection device disclosed in Japanese Patent Unexamined Prepublication No. 5383/1990 is described with reference to FIGS. 3 and 4, where FIG. 3 shows a perspective view of the device while FIG. 4 shows a plan view thereof.
An inspection device P comprises an L-shaped base plate 21, an inspector body 22 and a cam 33. The L-shaped base plate 21 has a first holding plate 23 standing at one end thereof. The inspector body 22 is slidably mounted on the surface of the L-shaped base plate 21 and moved by means of the cam 33. The inspection device P further comprises a detector section 24 to detect incomplete attachment of a connector B to be inspected.
A first rectangular groove 23a is formed on the first holding plate 23 of the base plate 21, which the first groove 23a is similar in shape to a second groove 25a formed on a second holding plate 25 adjacent to the first holding plate 23. A pair of side-wall portions 26b and 26c are disposed on the surface of the second holding plate to form a third groove 26a of a connector catch 26 to receive the connector B.
The inspector body 22 is slidably supported by a pair of shaft 27, 27 as shown in FIG. 4. One end of each shaft 27 is attached to the side-wall portions 26b and 26c, respectively, and the other end thereof is attached to shaft fixture plates 28. Compression coil springs 29, 29 are wound around each shaft 27 in a similar manner as described in conjunction with FIGS. 1 and 2. The inspector body 22 is forced away from the side-wall portions 26b and 26c due to the spring force of the compression coil springs 29, 29. An engaging hollow portion 30 is formed on the surface of the inspector body 22 facing to the side-wall portions 26b and 26c to receive a front portion of the connector B. A plurality of inspection pins 31 are projected from the bottom of the engaging hollow portion 30 which are equal in number to the terminals (not shown) in the connector B. Each of the inspection pins 31 passes through a penetration passage (not shown) formed in the inspector body 22 and is forced toward the connector catch 26 by means of a spring member (not shown) such as a compression coil spring. A cam catch 32 is formed with the inspector body 22 at the side-wall thereof. A cam surface 41 of the cam 33 is urged and abutted to the cam catch 32 due to the spring force of the compression coil springs 29.
The cam 33 is rotatably supported by a cam fixture plate 34 standing on the base plate 21 and has a cam lever 35 extending from one end of the cam 33. To turn the cam lever 35 against the spring force of the compression coil springs 29 makes the inspector body 22 approach the connector catch 26. The detector section 24 is built at the diagonally opposite side of the base plate 21 to the cam 33.
The detector section 24 comprises a locking arm 38 and a connector presser bar 39. The locking arm 38 is rotatably supported by a pair of fixture plates 37 as shown in FIG. 3. The connector presser bar 39 contacts the rear end of the locking arm 38 and is arranged in the side-wall portion 26b in such a manner that it can be withdrawn in and projected from the surface of the side-wall portion 26b. More particularly, the connector presser bar 39 is projected into the third groove 26a when no connector is engaged with the connector catch 26 and a locking portion 40 of the locking arm 38 engages with the arm catch 36. On the other hand, the connector presser bar 39 is pushed away and withdrawn in the side-wall portion 26b when the connector B is completely inserted into the third groove 26a of the connector catch 26. In this event, the locking arm 38 is turned in the counter clockwise direction to release the engagement of the arm catch 36 and the locking portion 40.
Inspection of continuity of the connector B by using the above mentioned inspection device P first requires to attach the connector B to third groove 26a of the connector catch 26. Complete engagement of the connector B with the third groove 26a releases the locking portion 40 of the locking arm 38 from the arm catch 36. Subsequently, the cam lever 35 is turned against the spring force of the compression coil springs 29 to advance the inspector body 22 toward the connector B, following which the front portion of the connector B is inserted into the engaging hollow portion 30. When the front portion of the connector B is completely engaged with the engaging hollow portion 30, the inspection pins 31 contact the terminals in the connector B, respectively. The connector B and the inspection device P are thus ready for the inspection of continuity.
After completion of the inspection of continuity of the terminals, the cam lever 35 is turned in the reverse direction to remove the connector B from the inspector 22 with the spring force of the compression coil spring 29. The facing surface of the connector B to the engaging hollow portion 30 is away therefrom and the terminals are thus off the inspection pins 31 allowing picking the connector B out of the connector catch 26.
The above mentioned inspection devices accompany troublesome process to positively attach the connector to be inspected to the connector catch, to advance the inspector body until the communication between the inspection pins and terminals is completed, and to take the connector off the connector catch after completion of the inspection. Such multi-step process makes the inspection ineffective and time-consuming. In addition, the necessary connector catch on the base plate results in a large-scaled inspection device which can only be manufactured at a high cost.